Bidirectionally promoting assembly order for ultrastiff and highly thermally conductive graphene fibres
Li Peng, Ziqiu Wang, Yuxiang Qi, Gangfeng Cai, Yingjie Zhao, Xin Ming, Zizhen Lin, Weigang Ma, Jiahao Lin, Hang Li, Kai Shen, Yingjun Liu, Zhen Xu, Zhiping Xu, Chao Gao
Abstract
Abstract Macroscopic fibres assembled from two-dimensional (2D) nanosheets are new and impressing type of fibre materials besides those from one-dimensional (1D) polymers, such as graphene fibres. However, the preparation and property-enhancing technologies of these fibres follow those from 1D polymers by improving the orientation along the fibre axis, leading to non-optimized microstructures and low integrated performances. Here, we show a concept of bidirectionally promoting the assembly order, making graphene fibres achieve synergistically improved mechanical and thermal properties. Concentric arrangement of graphene oxide sheets in the cross-section and alignment along fibre axis are realized by multiple shear-flow fields, which bidirectionally promotes the sheet-order of graphene sheets in solid fibres, generates densified and crystalline graphitic structures, and produces graphene fibres with ultrahigh modulus (901 GPa) and thermal conductivity (1660 W m −1 K −1 ). We believe that the concept would enhance both scientific and technological cognition of the assembly process of 2D nanosheets.